Shock-absorbing device for vehicles



Feb. 23 1926. 1,574,214

F. L. O. WADSWORTH SHOCK ABSORBING DEVICE FOR VEHICLES Filed June s, 1922 4 Sheets-Sheet"1.

INVENTQR 3 KQJhAM ZZ Feb. 23 1926.

F. L. O. WADSWORTH SHOCK ABSORBING DEVICE FOR VEHICLES Filed June 8, 1922 4 Sheets-Sheet 2 Feb. 23 1926.

1.. o. WADSWQRTH SHOCK ABSORBINGYDEVICE FOR VEHICLES Filed June a, 1922 4 Sheefis-Sheet 3 Q .1 G F I. -lQ1 Feb. 23 192s.

. F. L. O. W AD$WORTH SHOCK ABSORBING LDEVICE FOR VEHICLES Filed Junks, 1922 4 Sheets-Sheet- 4:

5 FIE-3-25.

lN VENT 0R 9 {0. #W

the supplemental spring. systeintively resisting oscillatorymovcn'icnts ot' the Patented Feb. 23, 1926.

UNITED STATES- FRANK L. 0. WADSWORTH, or PITTSBURGH, PENNSYLVANIA.

snoox- -ansonnme nnvron "son VIilEIIGLESn Application filed June 8,

To aZZ whom it may concern Be it known that I, FRANK L. Oi Nanswonrn, a citizen of the United States, res ding at Pittsburgh,Pennsylvania, have invented a new and usetul Improvement in Shock-Absorbing Devices for Vehicles, of which the following; is a full, clear and eX act description, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to that class ofshock absorbing devices for vehicles which cushion and elastically absorb not only the effects of kinetic compression movement, but also the eilects of any rebound, or of any abnormal separation of the body and axle members, that mayresult from the passage ot'the wheels over the irregularities of. the road surface. This class of apparatus isgenericaliy distinguished from that which acts in one direction onlye. g, to soften-or cushion compression shocksbyz a much smoother and easier operation of the elastic suspension system, and more particularly by the elimination, or substantial abatement, of the objectionable tossing and pitching of the vehicle bOt i that results from an nnrestrained recoil of the suspension springs attcr severe compression.

One of the primary objects of this invention is to produce a double or dual restraint system of the functional character just in dicated, which will operate efi'ectively under widely varyingconditions of loading; and. which can be readily adjusted or modified so as to impose any refpiired degree of relative restraint or cushioning etl'ect on the opposed moveuicntsot the body. and axle parts toward and away from each other. present invention I accom 'ilish this-object by the utilization ot a combination of supplemental springs. one 0t winch. is n'ii'narilydesigned and adapted to directly resistlhe cmnpresi-iion of the resilient support system; and another of which is-dircctly el'iective in restraining the rebound orscparation. otthespring supported members. and isalso indirectly effective in controlling or governing; compressive movements. Any desired ratio between the reverse, or counter actions. of

in respecl'r-ody and axle members toward or away J! i .iroin each other -can then be obtained by a suitable,proportioning andarrangement ot the (htierent secondary elements of the In the 1922. semen-no. 586,911.

combination; in such manner, for example. as is CXQHIPllfiEtl inflfthcvarious illustrative ent hodiments described.

Another object of the present improvements is to provide a spring suspension system in which the supplemental resilient elements are so arranged as to ell'ect-ively resist and restrain any lateral displacementsuch oi? my invention hereinafter as side sway or rolling, or longitudinal pitchingot the vehicle tonneau on its running gear supports; and thus increase the steadiness of body movement and the ease and safety of driving.

A further ob ect of this-invention to provide a'supplemental spring unit, which issimple andself contained in structure, and

which can be interposed directly between an end of a main spring; support and that-part ot' the vehicle to which said end is ordinarily pinned or shackled, without; any change in the construction or relative arrangementor the standard chassis parts of V the vehicle. i

,Other ob ects and'advantages of various applications of my improved shock absorber sorberdevicc; Fig. 2 is a similar view of the same combination on the oppositeside oi the;

vehicle and shows the parts in the position of compression; F 3 another viewot' the construction shown in Fig. 1, men'ibers thereof in the position of extreme rebound; i is scale) of this samectnistruction; Fin 1s a diagram showingrthe relative posi ions 01"" the ends of the rebound restraint springat dil rent points in the normal oscillatorv mo ElllQlltOf the body and axle member Fig. (l .isan elevation of a seeond'embodimen-t otmyinvention as applied to the crossproved supplemental spring suspension and show the parts thereof in the positions which a plan View (on-alargd v with the they assume under normalload (Fig. 8) and under an increased kinetic compression stress .9); Figs. 10 and 11 are corresponding views of a fourth exemplification of my present improvements, and respectively illustrate the members of the suspen sion system in their normal loadand their rebound positions (and also in the dotted line position of extreme compression) and Figs. 12 and 13 are rear end elevations of opposite sides of a cross-leaf spring mounting similar in form to that illustrated in Fig. 6. but with a modified form of supplemental spring elements. i

Fig. lat is an elevation ofthe rear part of a side leaf spring mounting provided with still another form of my improved shock absorber construction; Fig. 15 is a similar view of this same structure with the parts thereof in a position of extreme compression; Fig. 16 is another elevation of a further embodiment of my invention as applied, in this case, to a front side leaf spring support; Figs. 17 and 18 are two side views of another exempliiioation of the present improvements and illustrate respectively the normal load position and the abnormal rebound position of the main and supplemental spring elements of the combination; and Fig. 19 is an elevation of a cantilever spring mounting that is provided with still another modification of my improved supplemental spring suspension.

Figs. 2021 and 2223 illustrate two forms of my present invention as adapted to the direct suspension type of supplemental spring supports (the S. S. S. type) for either cross-leaf or side-leaf main springs showing respectively the static load posi tion of the parts Figs. 20 and 22) and the kinetically loaded positions thereof; (Figs.

21 and Fig. 24: is another view of the construction illustrated in Fig. 23 and shows the members of that construction in the position of extreme rebound; Fig. 25 illustrates athird exempliiieation of my improvements as applied to the direct suspensiontype of organization; and Fig. 26 is a view of this last construction with the parts in the position which they assume under anincieased load stress. I

In the construction shown in Figs. 1 to 5, the eye ends of the cross leaf spring 1 are pivot-ally coupled to the outer extremities of twin arm levers 2-2, and the latter are supported on the axle brackets 33 by means of the twin shackle links l The inner ends of each twin lever member, 2, are elastically coupled to the axle of the vehicle by means of a pair of tension springs 5"5; and the intermediate portion of the said member is also resiliently connected to the body of the vehicle by means of cross bolts 6 and 8 and a single tension spring 9. The bolts 6 andS are so positioned that when the parts are in normal load position (F ig. 1) the axis of the spring 9 is in substantial alignment with the shackle pivot sup-port for the lever 2 and does not therefore exert any angular pull on the latter member. Under such conditions the normal load pressure on the outer end of each lever element is carried entirely by the initial tension in the supplemental springs 55.

lVhen the system is subjected to an increased kinetic load stress, or compressive shock, the levers are rocked outwardly from the position shown-in Fig. 1 toward that shownin Fig. 2. This im 'mses an in.- creased tension on the supplemental springs which therefore tend to cushion the compressive movement and resist the approach of the body and axle parts. The relation between the linear approach of the body and axle members and the angular movement of the levers 2-2 depend: on the relative fiexural resistances of the main spring and the supplemental springs, 5 5, and on the ratio between the short and long arms of the lever elements, with which these two elastic units are respectively connected. These operating parts are preferably so proportioned, that during the normal compressive movement (N to C) the distance between the bolt connections 6 and 8 is not substantially changed (see diagram of 5) and this movement does not, under these conditions, sensibly alter the initial tension of the auxiliary springs 9, 9. The movement does however change the position of these springs with respect to the levers and the latter are thereby subjected to progressively increased and oppositely directed stresses, each of which is equal to the initial tension of the resilient element 9 multiplied by the sins of the angle, a, between the axis of the said spring and the lever arm 2-6 (or 0 -0). The compression of the system therefore, concurrently increases the inward pull of both sets of springs, 55, and, 9-9, on the outwardly moving ele-n'ients 2-2; and also progressively increases the reactive outward pressure on the opposed body connections, 8-S. "Any lateral displacement of these connections, away from the vertical lines of movement N -C or any departure of the lever movements from the predesigned action depicted in Fig. 5,--which may change, or tend to change, the normal load length and the initial flexure of the springs. 9will thus be controlled and restrained to a greater and greater degree as the compression movement continues. The ,combined effect of the concurrent linear and angular motions of the parts, 8, 1, 2, (i and 9, is to exercise a continually augmented control on the compression movements which will prevent, or tend to nfevent, any unsymmetrical or dissimilar action of the two sides of the elastic suspension system, or any lit) ' stantially unchanged.

- lore take place without imposing 'ticn olstatic equilibriinn (or normal load K) is directly resisted by the tension of the auxiliary springs 9, 9, which are elongated by an amount that is substantially equal to the rebound movement NR. movement the angular position of the levers 2 2 will be only slightly altered from that shown in Fig. l and the normal tension in the springs 5, 5, will therefore remain sub The lever supports for the ends oi the main spring 1 are however i'ree adapt then'iselves to the natural movement of this primary suspension member. when it is temporarily relieved of strain by the rebound or relative upthrow of the vehicle body; and this movement can there any great d tee of reverse :tlexure or abnormal tanibcr on the said mam spring.

It will be noted thatthe lever and supplemental spring elements, 259, are so disposed with relation to the body'o'f the vehicle, that the latter is always subjected.during both compression and rebound movementsto two pair of oppositely and symmetrically inclined -forces which resist any lateral rocking or rolling movement and act to hold the spring suspended parts in centered position on the running gear members. Any transverse displace1nentin the plane of the main spring suspension is also, resisted by the upward movement of the main shackle links t on the side which is tending to move away from the center, with a resultant lifting of that side against action of gravity. The combined eilect centering actions is to efficiently restrain and quickly abate the objectionable and dangerous side sway that is induced l :y the rapid passage of the vehicle wheels over laterally uneven or irregular road surtact-s. or by turning corners at a high speed. This feature of my present invention is tllGi'QlOl'G of importance in increasing the sate as well as the comfort, of driving motor cars; and it is also conducive to the reduction ofthe lateral strain and distortion of the parts of the chassis frame.

The organization shown in Figs. 6 and 7 is substantially the same in general structure as that illustrated in Figsl to 5, save that the rebound-restraint spring is an open Jl till) out only the first set of supple During this coil compression spring instead of a closed coil tension spring. the secondary resilient member 9 confined, the desired initial or normal tei sion. between two headslO and 11; the iirs; of which is connected .to the cross bolt 6 by the two pivot bolts l2'12, and the second of which is coupled to the pin 8 by the single adjustable bolt 13 (see Fig. 7). The operation of this device is essentially the same as that of the first described construction: lVhen subjected to a compressive stress the lever arms 2' are rocked outwardly and the tension springs 55, are subjected to increased ilexure, but the sprin S) remains substantially I unchanged in length, and cooperates with the springs m s (in resisting unsymnietrical move ments or lateral distortions of the system during the approach of the-body and axle parts.) only by reason of its change in angular position fwith. respect to the lever element. When subjected to rebound or are pansion stress, the lever arms are not sensibly moved from normal or static load. position, but the spring 9 is subjected to a direct compression stress that is proport onal t the separation of the axle bracket 3 (which carries the parts 2-(i) and the body bracket that supports the pin f 8* (and its attached follower plate 11). In the complete organization each end of the main spring 1 is supported in the manner shown in Figs. 6 and T and the body of the vehicle is at all times maintained in centered position on its axle and running gear supports by the symmetrically and obliquely inclined actions of the twin pair or" lever and spring elements (2?5'-9) on the opposite sides of the chassis frame.

In the construction illustrated in Figs. 8 and 9, the levers 2 2 are pivotally supported at their outer ends on the reversed,

axle perches 3' 3 and are shackled at intermediate'pomts in their'length to the ends ot the main spring 1. 'The inner end of each lever is provided with a T-shaped headf 14. that engages the upper ends of a pair oi twin volute compression springs 5", disposed one on'each side of the main spring 1; ain the lower extremities of these supplt-inientai coil elements are sup 'iorted on asaddle bracket 15 that is cli 'iped to the said main spring. T he lever elements 2" are also providcd with iorhed earsto receive the cross bolts, 6", that are pivot-ally engaged with the lower ends of U-shaped leai spring shackles 9"; and the opposing ,remities of these resilient shackles are flexibly coupled to the body brackcts,*l6, 16 by means of the pintle bolts 8", 8.

In this arraugemerrtv In the normal or static'load aosition or the parts the initial tensions of the springs o maintain the lever elements 2 in such position that the sprng terminals 6"8" are in substantial alignment with the axial supports of the lever elements (see Fig. 8). But when subjected to an increased kinetic load, or compressive shock, the levers 2 are rocked inwardly and downwardly, thereby imposing an added 'fiexural strain on the volute springs 55 and also changing the angular position of the spring shackles 9" with respect to the lever arms to which they are attached. These concurrent angular movements of the element" 2" and 9 will ultimately brin them to the position shown in F 9; and further compression of the system will, in this case, impose an increased liexure on the elastic units 9 as well as on the units 5". The approach of the body and axle parts is thus resisted, and also concurrently controlled or governedin the manner heretofore explained -by the conjoint and cooperative actionof all of the supplemental resilient elements,5-5, 9 -9 although the initial tension of the latter springs (9) is not substantially altered during the major portion of the said movement. But in the reverse rebound movementabovc or be yond normal load pos'tionthe spring shackle elements 9 9 are pulled open by an amount that is substantially equal to the said rebound; and the upthrow of the body therefore directly restrained and checked by the elastic resistance of these curved leaf spring members. In this case the body is maintained in its central, or normal, position on the axle supports, both by the oppositely directed pulls of the connected lever and spring elements 2"9" (on the conjoined chassis members 3"-16), and also by the symmetrically and obliquely inclined thrusts of the tens'oned volute coils 5 (against the opposite sides of the main spring 1).

In the construction shown in Figs. 10 and 11 the relative arrangement of the suspension levers, 2-2, and of the supplemental springs 5 (with respect to axle and main spring members) is the same as in the last described organization; but the said elements, 5, are in the form of multiple leaf springs, which are bolted at their outer ends to the lever members,'2', and are slidably supported at their inner ends on the upper leaf of the primary spring member 1. The rebound-restraint elements 99 are also made in the form of multiple leaf springs which are bolted to rigid arms 13 3", that are pivot-ally mounted on the body bracket cross bolts S 8, and are connected to the lever cross bolts 6 -6 by means of the links 12-12-the various operative parts being so proportioned and arranged that, in the normal load pos'tion (Fig. 10), the lines of connection 126, between the .sp 'ing and lever elements 9 2 intersect the pivot sup ports for the said levers. lVhen the system is subjected to an increased kinetic load, or compression stress, the parts are moved from the full line, stat c load, position of Fig. 10, toward the dotted line positions C-0 of Fig. 11. This movement flattens out the supplemental leaf springs, 55, and

roves the links, 1212', to an inclined position with respect to the lever arms 2- thus subject'ng the latter to a tangential component of the initial tension imposed on the bowed leaf springs 9 without sensibly altering that initial tension. When the parts rebound or separate beyond normal load position (Fig. 10) and move toward the positions, R 7, shown in full lines in Fig. 11, the loci of the lever elements, 22 (and the lle-Xural strain on the supplemental resiient ele nents 5 5), is not sensibly changed; but the links 12-12 are subjected to a direct pull which flattens out the leaf springs 9-9, and thus imposes a progressively increased restraint on the .supernormal expans'on of the system. In this case the resistance to rocking, or to relative lateral displacement of the body and axle members, is afforded by the symmetrically and obliquely inclined forces that are transmitted from the tensioned springs 9 9 trirough the l'nks 12- -12 to the inwardly and oppositely inclined lever arms 2 -2"; and this resistance to side sway becomes progressively greater as the rebound movement increases.

Figs. 12 and 13 depict another supplemental leaf spring suspension wh'ch is structurally analogous to that shown in Figs. 8 to 11 inclusive. In theconstruction now under consideration the lever elements, 2 -2 each carry two multiple leaf springs 5 and 9 which i are rig'dly bolted thereto, and

which are respectively connected, at their inner extremities, to the bocy of the vehicle by the shackle links, 15 and 18. When the system is subjected to kinet'c compression stress the members are moved from the position ofstatic equilibrium (Fig. 12) toward the position C-c shown in full l nes in Fig. 13. In this movement the supplemental leaf springs 5 are flattened out; and the link connections 13 are swung through an angle, .2, thereby subjecting the lever elements 2 to corresponding tangential components of the iuit'al tensions imposed on the secondary springs 9, 9. When the parts are subjected to rebound strcss--and move from the full line positions of Fig. 12 to vard the dotted line positions R'/' of Figs. 12 and 1lthc shackle connections 13 exert a direct longitudinal pull on the bowed leaf springs 9 and straighten them out to the form shown at the left of Fig. 12 (dotted lines), thereby imposing a reactive restraint on the separation of the body and axle members. During the first stages of th's rebound movement the angular positions of the lever arms 2 (and the corresponding fiexures of the supplemental springs 5) are not substantially changed; but when the system is subjected to an excessive expansion, the links 15 may be brought into substantial alignment with the pivotal supports of the levers, and the secondary leaf spring elements, 5, may then be subjected to a direct longitudinal pull, that will likewise tend to straighten them out in the manner more fully described in my 'copending' applicat'on, Sci. .No. 551674, filed April 11th, 1922. Under such circumstances the abnormal separation of the body and axle members will be resisted and checked by the cooperative and conjoint action'of both sets of supplemental leaf springs it and 5; and the side sway of the body on the running gear \v ll also be effectively re strained, or prevented, by the centering action of the oppositely and syi'nl'netrically inclined tensions of these longitudinally stretched resilient elements. 7

Figs. ll and 15 illustrate the application of my invention to a rear side leaf spring support. In this exemplihcation of my iinproved shock absorber construction, the outer end of the primary suspension member 1 is coupled to the syroll body bracket 3 by means of a radius guide link 17, and a clip 18; and is also shackled to the intermediate part. of a lever 2 by means of the coupling block 19 and the links 4 The .outer extremity 'of-the lever 2 is forked and pivoted directly on the end of the scroll bracket 2-3 and the inner extren'iity thereof adjustable r 12 The larger end of the vo'lutc coil 5 is supported on a forked hrachet 1-3 that flexibly carried by the i 1- axle block and by an intermediate part or the main spring 1 and the base of the supplen'iental leaf spring 9 is rigidly bolted to the said axle block. The bracket 15 is also provided with an elastic bumper block 20 that bears on the intermediate portion of the leaf spring 9" and supplements the elastic rcs' tance of the latter to increased fieXnre.

The operation of this last described or- ;ranizatidn is as follows: lVhen the body and axle membcrsare forcedton'ard each other. b2 a kinetic increase in load stress, the lei cr 2 will he rocked in a counter-clockwise direction (toward the position shown in Fig. 15), thus compressing the supplemental spring against its bracket support 15, and moving the link-12, in the opposite direction, through an angle 2; p he resistance to the compression movement will then be the imposed or added tension in the spring 5 plus that con'ipone'ntof the tension in the s ring 9, which acts transversely to'the arms or": the lever 2. During this movement, the outer eve endof the main spring 1 is constrained to follow the arcuate path dc sci-ibedby' the inner extremity of the radius guide link 17; and this link element is so prop'tirtioned and positioned, as to make this are conform to thenatiiral path traversed by the said i e as the primary suspension member toward the body and flattens out undei" the increased load stress. But when the link 17 has reaclied the position 0, (indi cated in dotted lines in F 14 and in full lines 15), the further relative separation of the parts, 3 -18 and 1 19', is arrested\vith a corresponding suspension of theangular counter-clockwise movement of the levei '--and further approach of the body and axle members is thereafter mainly resisted by the flexurc of the main spring alone. When the members have returned to normal load. position (F ig. 14) the radius link 17 is in substantial alignment With the axle block connection to the main spring 1 and the link l2 is also in substantial alignment with the pivot connection between the lever 2 and the body bracket3 hen the parts are subjected to rebound stress which tends to move them toward the dotted line positions R'r of Fig. 1lthe pull of the aligned lever. and link elements 2 12" on the We end of the supplemental leaf spring 9 imposes an increased bending strain on the latter; While the pull ofthe radius link 17 onthe eye end of .the main springconcurrently imposes a longitudinal strain on this resilient member that tends to stretch and straighten out its inner and the flexed secondary spring 9 in restraining and quickly checking the expansion or separation of the body and axle parts of the vehicle; V i

p The construction shown in Fig. 16 is one which is particularly designed for the elastic support of the front axle of fl lnOtOl' vehicle. In this case the front end of an ordinary side leaf spring 1 is uncoupled from the adjacent extremity of the body horn Z3 and is pinned directly to one vertex of a triangular, or Tshaped, lever member 2 and the latter is, in turn, pivotally n'ioi'i'nted,"a't its center; on a special bracket 21 that is bolted to the said body horn. The ad acent upper vertex of the lever termii'rates in a head, 1%; that engages With the upper end of a volute compression spring 5[ recessed head 15 that is carried by the axle block and the adjawnt portion of the attached main spring 1 The lower vertex of the lever member is provided With a cross bolt (i that is connected to one arm of a bell crank arm 13 bymeansof thelink12j and this part of the said lever is further provided with across roller 22' that normally bearson the under side: of the main leaf spring 1 The bell crank arm 18 is pivoted on-- the axle frame at .8, and is his 'it' the bearings become worn, and alsoto assist the action of the supplemental spring in maintaining the parts in the normal load position that is shown in full lines in Fig. 16.

lVhen the structure illustrated in this figure is subjected to an increased load stress the relative approach of the main spring and body parts, l and'3--2l, rocks the lever element in a counter-clockwise direction and compresses the supplemental spring 5 between the downwardlymoving head let and the upwardly lifted bracket The ielat-ive angular and linear movements of the parts i and 8"13 swings the link 12 into the position c r' (dotted linesiand the initial tension of the secondary spring; 9 is then brought into play to assist the compressed supplemental spring 5 and the compressed buiier block in cushioning and restraining the further compress on of the system. When-the members rebound or separate beyond the, normal load positien and move tbward the positions shown in the dotted lines Rr of Fig. 16the engagement of the roller 22 with the under side of the main spring 1 carries the lever 2 to the same position as it occupies when the system is compressed to the position C-c. rebound movement does not result in any substantial compression of the coil Fi because the bracket support therefor moves downward with the main springbut it does exert a pull on the link connection 12 that. rocks the lever 13' in a counter-clockwise direction on its pivot support 8', (to the dotted lines position r r--r) and thereby Vcompresses the auxiliary coil 9'" against its seat lti This actionwhich is supplemented by the concurrent con'ipression ot the elastic butter 25imposes a progressively i creasing rest aint on-the vertical separation of the body and axle parts (beyond normal load position) ;and the interconnected membcrs I Q term a longitudinally still radius rod system that holds the axle in lllOliGl spaced relationship to the body horn and bracket, 3 2i, and resists,or preventsa any cndwise pitchingot the tonneau frame on running; gear supports.

'Figs. 17 and 18 illustrate another application of my improved shock absorber construction to thesuspension of either a rear oi a front side leaf spring. In the arrangeman here shown a T-shape l lever--so air This what similar in form to that depicted in Fig. 16is pivoted, near its center. on the body bracket or horn 3 and is connected at its outer end with the extremity of the main spring 1 by means of the extension saddle 19 and the shackle links The inner arm of the T head is bolted to the base or". the supplemental leaf spring which is shackled at its opposite extremity to the axle bracket 15 by means of the links 15 The central leg of the lever 2 is provided with a cross roller 22 which is normally in engagement with the lower side of the main spring, and is also provided with a cross bolt 6 that is coupled to the outer end of a powerful tension spring 9 by means of the adjustable link 12 The conjoined extremities of the spring 9 and the link 12 are supported and guided by the swinging arm 26 which is pivoted on the bracket 15 and the inner end of the auxiliary coil spring is tlexibly secured to the axle block assembly. A. second coil spring 20 is flexibly secured at its opposite extremities to the cross bolt 6* and tothe intermediate part of the supplemental leaf spring 5 and serves to reinforce the latter against increased llexural strain.

\Vhen the body and axle members 3 and are forced toward each other, by a kinetic compressionshock, the lever 2 is rocked in a clockwise direction; the supplen'ienta'l leaf spring 5 is flattened out; and the coil spring 20 is elongated; as shown by the dotted lines cc-C of Fig. 18. This liovement does not sensibly alter the normal tension of the spring 9 but it" rocks the link 12? through an angle 2 and thereby subjects the lever 2 to a tangential component of. this normal tension; and any further approach of the spring supported parts will thensubject the tension coil 9 to augmented tlexure, which thus cooperates with theincreased'strain in the resilient elements and 20 in resisting and checking the compression of the system. On -rebound movement. the separation of the body and axle parts exerts a longitudinal pull on the aligned lever and link elements 2 '12-, which swings the {guide lever 26 toward the left and elongates the heavy tension spring 9 In this case also the pressure of the main spring 1 on the roller 92 will tend to move the lever 2 in the same direction in which it is rocked by the compression oi the system; and this movement. will tend to further eloinrate the rebounil-restraint clemerit 9 and thus quickly arrest the abnor mal expansion of the spring supported iiiarts.

. Fig. '19 illustrates the application of an other form of my improvements to a main cantilever spring suspension for the rear axle of a motor'vehicle. In this embodiment of nix invention the end of the main spring 1 is coupled to the outer extremity 0151a lever 2 by means of the saddle 1.9 and till ill

the shackle links l This lever is pivotally supported, at an intermediate point in its length, between theforks of a radius rod member-27,,that connects the rear axle with a bracket 28 on the body frame; and it is rigidly bolted at its inner end to the base of a supplemental leaf spring 5 that is slidably engaged with the llllClQISlClQ of the main spring 1 The lever member 2 is also provided with upwardly extendingarms which carry a trunnion bolt (i that 1s at tached to a head 10; and this head is centrally perforated to receive a U bolt 13, which is pivoted at its upper end on the body bracket 16 (by-means of the crossbolt 8) and is adjustably secured at 1ts lower end to the follower plate 11. A strong compression spring 9 is confined, at suitable initial tension, between the head 10 and the plate 11. When the body moves toward the axle (from the full line normal load position N toward the dotted line position Ccc-) the lever 2 is rocked in acounter-clockwise direction on theradius arm support, and the supplemental leaf spring 5 is flattened out against the under side of the downwardly moving main spring 1 The downward movement of the body bracket is, and the concurrent angular movement of thevlever 2. also swings the parts 9 --.1O11 and 18 into the dotted line position shown at the left of Fig. 19; and the supplemental coil spring 9* then exerts a tangential or transverse thrust on the upwardly extending; lever arms, thereby assisting the action of the flexed leaf spring 5 in restraining and checking the further compression of the sys tem. When the parts return to normal load position the axis of the initially compressed coiltspring 9 is substantially in line with the main pivot support of the lever 2; and any rebound,- or further separation, of the spring connected members is then dlrectly resisted and quickly arrested by the correspondingly increased compression of this secondary resilient element, without lmposing any strain on either the supplemental leaf spring 5* or the main cantilever spring. 1. p

All of the constructions heretofore considcred comprise, or include, lever elements that are interposed between the main resilient members of the suspension systems and those supplemental elements thereof which are particularly provided to resist compression movements; the purpose of such interposed connections being, in general, to multiply or magnify theeffect of the linear approach of the body and axle spar-ts. But my invention is; also. generically applicable to the direct suspension type of shockabsorber construction. in which part or portion of the main spring is directly carried on a supplemental cushioning spring; whose fiex u-- movements aretherefore,"

be same in amount as those of the main spring part to which it is attached. The fourth sheet of my drawings illustrate three forms of such construction, in which the lever element of-the combination plays no part in determining or influencing the primary and direct action of the supplemental suspension spring (in cushioning and absorbing the effectsfofscompressive shock), but serves only as a means for controlling the secondary effect of the reboundresisting spring (in supplementing the action of the first mentioned spring).,'and for conjoining the said elastic rebound check element with the relatively, movable members of the chassis frameQ In the organizationshown in Figs. 20 and 21, the ends of the main spring 1 are directly coupled to the forked extremities of link arms 3030 which pass through the slotted feet of L-shaped brackets 31 that are bolted rigidly to the axle perches 3 The upper ends of these links terminate in heads let that engage with the adjacent extremities of the supplemental suspension springs 5; and the lower extremities of these springs are carried by the recessed feet 15 of the brackets 31. The heads 14 are pivotally connected to intermediate points of the levers 32-, which are rockably supported on the vertical legs of the brackets 31, and which serve as radius guide links for the said heads. These levers are forked at their inner ends, and are there provided with cross bolts 6 which engage with the central eyes of eccentri'cally coiled spiral springs 91; and the latter that are flexibly supported on the body lorackets-16 bythe bolts 8.

NVhen the body and axle members are.

forced toward each other by a kinetic increase in load (i; e.,-a compressive shock), the parts of the suspension system move from the full line positions of Fig. 20 toward those of Fig; 21. In this movement the supplemental suspension springs 5 are directly comprcssedbyan amount equal to'the relative movement between the axle and the ends ofthe main spring member 1 -andthe levers 32 are rocked inwardly through an angle,e, thusbringing theinitial tensions in the eccentric coil springs 9 into play to aid in resisting the approach of the body and axle parts. \Vhen the system has recoiled to normal load position the transverse compression axes of the spiral elements 9 are in substantial alignment with the axes of the levers andany rebound (i. e., any further separation'of the body and. axle members), is then directly resisted and quickly checked by the increased"transverse tleXure of the spiral coils, without sensibly altering the normal compression of the suspension springs 5 The longitudinal tens-ions in the oppositely and symmetricallyinclined connections; (32-e-.6- -)-s-;8 between the axleinc are mounted in ri-ngs'll and body brackets (3 "31 and 16 also holds the touneau of the yehicle in abalanced and centered position on its running gear supports and restrains, or prespring are pinned, as before, to the lower forked extremities of connecting rods 30 which are adapted to slide longitudinally through the heads l5 'of bracket frames 31 and which are guided in their longitudinal movement by parallel motion radius links 33S4t that connect the extremities of the said rods with the said frames. The frames 31" are in this case pivotally supported on the axle perches 3 and are provided with forked extensions 82 that are adapted to carry the trunnions 6" of recessed heads 10?. The heads 10' are apertured to slidably re ceive the legs of U bolts 13" thatare pivotalvlv supported, at their upper ends on the cross bolts 8 of the body brackets 16, and are'secured at their lower ends to the heads 11". A pair of volute suspension springs 5 are interposed between the-upper caps, 149, of the rods 30 and the heads 15 ot' the rocking frames 31*; and a second pair of similar springs 9 are confined, at a. suitable initial tension, between the heads 10 and 11 l Vhen the main spring and body members are forced toward the axle the supplemental suspension springs 5 are further compressed; 'and'the concurrent increased bending and flattening of the main spring 1 rocks the pivoted frames 31? inwardly toward the position shown in full lines in Fig. 23. This rocking movement swings the U bolt frames 13 and the secondary coil springs 9 associated therewith ---"to an oblique position with respect to the arms 32 of the frames 31*; and the initially tensioned elements 9' then exert an outward thrust on the heads 10 that serve to supplement the increased fiexureof the suspension springs 5 in cushioning and absorbing compressive shocks. When the parts have returned to normal load position the axes of the secondary coils 9 are in substantial alignment with the pivot supports of the frames 8 32; and any rebound or expansion of the system carries the members toward the full line position of Fig. 24. This movement imposes correspondingly increased flexures on the secondary springs 9 andthe abnormal separa ion of the body and axle parts-as well as any lateral displacement or relative side sway of these parts-is thus strongly resist- (-d and quickly checked.

The construction shown in Figs. 25 and ?6which is particularly designed for the rear axle suspension of a Ford car-is itructurally analogous to that shown in (32) carry a cross bolt 6; and this cross bolt is elastically coupled to a body bolt, 01' bracket, 8, by means of the open coil tension spring 9. The frame 31 is, in this case, pivotally supported on the brake drum bracket 3; and a direct suspension spring 5 is interposed between the cap 14 of the link bar 30 and the base 15 of the swinging frame. \Vhen the body and axle members move toward each other--from the normal load position of Fig. 25 toward the position shown in Fig. 26-the suspension r-oils 5, at-the opposite ends of the main spring, aresubjected to augmented compression,and the concurrent increased flexure and flattening of the main spring rocks the support frames 31 inwardly. The combined downward movements of the heads 14 and the inward angular movements frames "31 carry the cross bolt connections 6 to such positions with respect to the connections 8 that the initial tensions of the 'coilsprings 9 also become effective in resisting the approach of the body and axle members. ,l/Vhen the parts have returned to normal load position (Fig. 25) the forked extremity of'the link bar 30 engages with of the i the-base ofthe frame 51' (thus preventing any further expansion of the suspension springsb) and the axis of the tension coil 9 is then in substantial alignment with the pivot support of the said frame on the bracket 8"} Under such circumstances any rebound movement is directly resisted by the increased flexural strain thereby imposed on the springs 9; and the symmetrically and obliquely directed pulls of these stretched resilient elements, on the opposite sides of the vehicle body, is also effective in restraining or preventing any lateral displacement or the chassis members.

The foregoing description of various illustrative embodiments of my present invention will enable those skilled in this art vertically oscillating to recognize and appreciate the basic and forms of resilient suspension systems that may, as desired, present all, or only a part, of these characteristic features. The severerner i al specific embodiments that I have depicted and described as generically representative of my improved dual restraint suspension system also present certain individual features of structure or functional action that may be most advantageously utilized in conjunction with certain forms of main spring supports; and with the foregoing disclosure as a guide, those who are familiar with or ganizations of this character, can, in any particular case, readily determine and apply that specific exempliiication of my improvements that is best adapted to meet the particular conditions involved. For these reasons I do not wish to be understood as restricting myselt to any of the hereinbefore disclosed constructions as presenting a preferred form of my inventionaor as limiting myself in the scope and application thereof except as may be indicatedin the appended claims.

I claim:

1. In an elastic suspension system for vehicles the combination of a rocking member, a plurality of springs operatively connected thereto, and means for effecting a substantial change in the angular position of the said member with respect to the flexural axis of one of said springs without substantially altering the initial tension of the letter. substantially as described and for the purpose specified.

In an elastic suspension system for the relatively movable parts of a vehicle chassis, the combination of a plurality of springs, a

rocking member oporatively connected with v one of said springs and wlth one of the said relatively movable parts and a system of connections conjoining another 01. the'said springs to the said member and to the other of said parts, whereby the angular relationship ot the rocking i'nember and the last mentioned spring is progressively changed without substantially altering the initial tension of: this spring when the chassis parts move from normal load position toward each other.

V 3. In an elastic suspension system of two relatively movable parts, the combination,-

of a rocking memberpivotallyamounted on one oi said parts and operatiyely connected to the other part, aspringattached" at one end to the said member and ad aptedoto be progressively tiered when. thel'member is rocked on its pivotal-support, and a second spring; ,conjoining the rocking member" and one of said niovable'parts' and ada nted to be progressively flexed withont any substantial; inci ement-of l'said member when .the'";p'ai'ts separate beyond normal position.

l. In a spring suspension-system for .ve-

hicles the combination'ot a spri '5', lever elementpivotal-ly mounted on jone ofthe relatively {movable n'leiiib'ers of: the y hicle;

an DP? ve y. 01.

sion movement of the system and means for in'iposing an increased flexure on one of said springswitliout substantially altering the normal or initial tensionot the others when the system expands beyond normal load position. I

6. In an elastic suspension system -fortwo relatively movable members the combination oi a plurality of springs, means for operatively 'coni'iecting fsaid springs with said members, means for increasing the normal I or initial tension of oneot said springs and for concurrently altering the angular position of another of said springs without sub-v stantially changing its initial tension when the movable members are forced toward each other, and nieanstor increasing the initial tensiono t the last mentionedspring without substantially altering its position when the HIGIDbQTS are separatedbeyond normal load position. a

T. ln anelastic suspension system for yehicles the combination of a main spring a plurality of supplemental springs cooperating therewith, means for changing the angular position of one of said springs without substantially altering the initial r lexure thereof when the system is subjected to compression, and for changing; the initial fieX ure of this same spring 'without substantially altering its angularposition when the system issubjected to rebound stress. 7 8. An elastic shock absorbing; device for vehicles which comprises a plurality of spring elements, means for separately eonn'ectin'g each of said elen'ientsto the body or to the axle members of the vehicle, means to r altering the angular relationship of certain of these springs with respect to its associated vehicle members when the parts are qlisplaeedin one direction from normal load position and for progressively increas inn; the initial flex'ure ofthese same springs without substantially altering the angular position thereoi' (when the vehicle parts are displaced 1 the other directioiiffioiin normal positionf elastic suspension system for yehicles 'Iwhich, comprises the combination of a main sprin "siippl mental spnngnmans means for altering the angular position of this second spring without substantially changing its initial tension when the system is compressed, and for increasing its initial tension without substantially altering its angular position when the system' is expanded beyond normal load position.

10. In an elastic suspension system for vehicles the combination of a compression resisting spring for restraining relative vertical movements of the body and axle members toward each other, a rebound check spring for resisting a vertical separation of the said members beyond normal load position, and means for shifting the line of action of the said rebound-check spring during approach 1novoments and thereby imposing an increased restraint on relative lateral displacements of i the moving members.

11. in an elastic suspension system for ve- I hicles the combination of a plurality or springs interposed between the relatively movable body and axle members thereof, with means for increasing the flexure of one set of springs to thereby restrain relative ure of the compression resistingspring and" to concurrently alter the position of the rebound chech spring, and thereby augment the control of the system on both vertical and lateral oscillations of the relatively movable vehicle members.

13. In an elastic suspension system for two relatively movable members the combination of a lever pivotally supported on one of the said n'iembers, a spring flexiblymounted on the second of the said members and connected to the said lever with the line of connection normally intersecting the pivotal support therefor. a second spring interposed between the said lever and one of said members with its line of liexure inclined at a large angle to the longitudinal axis of the.

said lever, and means. conjoining the said second member with the lever and acting to rock the latter and to concurrently increase the tlexure of the said second spring when the members are moved from the position of static equilibrium toward each other.

ll. .th shocl; absorber organization for vehicles whiehcomprises a lever pivotally sup ported onone of the vehicle members, a sup 'plemental compression resisting spring connccted to the said lever with its axis of flexurc lnclmed at a large angle thereto, a conplmg element con o1n1ng the lever-supplemental-spring-assemlolage with another of with its axis of flcxure normally intersecting the pivotal support therefor and acting to directly oppose any separation of the said members beyond normal load position.

15. A spring suspension system for vehicles which comprises a' main spring, a supialemental spring cooperating in series there with to resist the approach of the relatively movable chassis members, a lever element pivotally supported on one of the said 1ne1nbers, an auxiliary rebound check spring flexibly attached to another of the said members and connected to the said lever with the line of connection normally intersecting the pivotal support therefor whereby the said auxiliary spring may be maintained under a predetermined normal flexure without exerting any rotative stress on the said lever, and means for rocking the lever on its pivotal supportwhen the main and supple-- mental spring elements are cooperatively flexed by approach movements and thereby altering the relative'positions of said lever and said rebound-check spring without sub-.

stantially changing the normal flexure of the latter.

16. In a suspension system for two relatively movable members the combination of a main spring rigidly supported on one of said members, a lever pivotally supported on the other member and flexibly coupled to one end of the said main spring, a supplemental spring operatively associated with the said lever and acting in series with said main spring to resist and check compression movements of the system, an auxiliary spring conjoining the main spring supporting member and the said lever with its axis of fiexural strain normally intersecting the pivotal support of the lever and acting to directly resist any rebound or separation of the said members beyond their position of static equilibrium.

17. In a spring suspension system for rehicles the combination of a main spring I rigidly supported on one of the chassis members thereof, a lever element pivotally mounted on another of the said members and flexibly coupled to one end of the said ma n spring, a supplemental compression resisting spring interposed between the said leverand an intermediate flexible part of pthe said main spring, and an auxiliary rccl c l eclr.v spring conjoining the main mg support ng member and the level lilO element with its line of flexural action normally intersecting the pivot support otthe lever and so positioned with respect thereto that the relative motion of the conjoined parts during compressive movements does not sul'istantially alter the normal initial flexure of the said rebound-check spring.

18. A shock absorber organization for the relatively movable chassis members of a vehicle which comprises alever element pivotally mounted on one of the said members, a coupling element conjoining said lever with a second relatively movable chassis member and acting to rock the lever on its pivotal support when the said members are moved from normal load position toward each other, a supplemental compression resisting spring operatively connected with the said lever and adapted to resist the rocking movement thereof, and a rebound check spring connecting the said lever and the said second chassis member, the said rebound check spring being so positioned with respect to its connections that it is normally maintained under a substantially constant initial fiexure when the lever is rocked on its pivotal support during compression movements and is subjected to a progressively increased flexure when the connected parts are separated by a rebound movement beyond the normal load position.

19. In a spring suspension system for two relatively movable members the combination of alever element pivotally supported on one of the said members, means for rocking the said element on its pivotal support when the two members are moved from the position of static equilibrium toward each other, a spring having its flexural axis inclined to the line of said movement and adapted to resist the rocking of the said lever, a second spring flexibly connecting theother of the said members with the said lever and so positioned with respect thereto that the line of connection normally inter sects the pivotal support for the said lever and is progressively inclined to the axis thereof as the said members approach each other.

20. A shock absorber organization for two relatively movable members which comprises a spring having its flexural axis inclined to the line of movement therebetween, a lever pivotally mounted on one of the said members and operatively conjoined with the said spring, a second spring connecting the said lever and the other of the said members with the line connection normally intersecting the pivotal support of the lever, and

means for progressively shifting the said line of connection relative to the said line of movement when the members approach each other and for maintaining it'in substantially fixed relationship thereto when the members are separated beyond the position of static equilibrium.

21. In a spring suspension system for two relatively movable members the combination of a pair of levers pivotally mounted on one member and symmetrically positioned with respect, to the other, means for concurrently moving the said levers in opposite directions when the said members approach each other, a pair of spring units having their flexural axes symmetricallyinclined with respect to the line of movement between the said members and adapted to be progressively'flexed by the movement of the said levers, and a second pair of spring units connecting the levers and the second of the said members with the said lines of connection normally intersecting the pivotal supports for the said levers, both sets of said springs being adapted to continually restrain any sidewise displacement of the said members with respect to each other.

In testimony whereof I have hereunto setmy hand.

FRANK L. O. 'WADSWOR-TH. 

